Question

The output voltage of a transformer connected to a 220 V line is 1100 V at 2 A current. Its efficiency is 100%. The current coming from the line is:

• A. 20 A
• B. 10 A
• C. 1 A
• D. 2 A

Hint:

In an ideal transformer, the power in the primary coil equals the power in the secondary coil, and the currents are inversely proportional to the voltages.

Answer 1

The Correct Option is B

Step 1: Use the power formula.
The power in the primary coil is equal to the power in the secondary coil (since efficiency is 100%). \[ P = V \times I \] Thus, for the secondary coil: \[ P = 1100 \times 2 = 2200 \, \text{W} \]
Step 2: Calculate the current in the primary coil.
Using the power equation for the primary coil: \[ P = 220 \times I \] Solving for \( I \), we get \( I = 10 \, \text{A} \).
Final Answer: \[ \boxed{10 \, \text{A}} \]